Add registry kind indexes and entity pages.

CONTENT-WP-0002-T02 reads kinds from each snapshot and serves both example dataspaces without oncology imports.

Assistant: grok
Assistant-Session: 01a1346c-fdff-7741-b1af-b7283661554b

ui/components/EntityDetail.test.tsx

@@ -0,0 +1,26 @@
+import { renderToStaticMarkup } from "react-dom/server";
+import { describe, expect, it } from "vitest";
+import { findEntity, findKind } from "@/lib/catalog";
+import { EntityDetail } from "./EntityDetail";
+import { KindIndex } from "./KindIndex";
+
+describe("kind and detail views", () => {
+  it("renders the registry plural and a linked record", () => {
+    const kind = findKind("software-architecture", "concept");
+    expect(kind).not.toBeNull();
+    const html = renderToStaticMarkup(<KindIndex kind={kind!} />);
+    expect(html).toContain(">Concepts<");
+    expect(html).toContain("Coupling");
+    expect(html).toContain('href="/software-architecture/concept/coupling/"');
+  });
+
+  it("renders the entity title, an unknown claim, and a neighbour", () => {
+    const entity = findEntity("systems-thinking", "concept", "system-boundary");
+    expect(entity).not.toBeNull();
+    const html = renderToStaticMarkup(<EntityDetail entity={entity!} />);
+    expect(html).toContain(">System boundary<");
+    expect(html).toContain("formal-measure");
+    expect(html).toContain("unknown");
+    expect(html).toContain("Stock and flow model");
+  });
+});